Guide to flat roof materials
Flat roofs are great for sheds, garages or extensions and come in a wide range of different materials – find out about the options here.
If you’ve recently built an extension, or are finally fixing up that leaky shed or garage roof, then you might want to look into getting a flat roof installed. Living in the UK means heavy rainfall is always going to be an unfortunate problem, but a flat roof is specially designed to prevent weather damage – so you can get rid of those irritable leaks once and for all. With a flat roof you also don’t have to worry about loose tiles or peeling paintwork – in fact, there is hardly any maintenance required whatsoever.
Laying a new flat roof can be completed by a team of professional building contractors, but before you get stuck in you will need to decide on a suitable roofing material for your property. Think carefully about the type of building you have (i.e. domestic or commercial?) and estimate how long you ideally want the roof to last before any repairs will be necessary, as cheaper options aren’t guaranteed to last forever. You should also remember to budget carefully, and spend no more than is necessary – you don’t want to pay out for industrial strength felt if all you need to do is fix up an old garden shed, for instance. If you’re unsure of the materials available, here is a quick outline of the more popular options:
- uPVC flat roofing – this chemically produced plastic (also known as Polyvinyl Chloride) proves to be a strong and durable roofing material, but is best suited to smaller buildings such as sheds and garages which don’t have a huge surface area. Its heat-welded seams ensure the roof is more than 99% watertight, and a coating of special plastic resin also makes the plastic extremely fire resistant. Cheaper options have been found to go brittle over long periods of time, so you should also make sure you purchase a product that has been injected with additional plasticisers to improve the roof’s elasticity. This is vital to prevent sagging under heavy rainwater and only costs a little extra – altogether uPVC roofing will cost only around £30 to £90 per square metre. The only major drawback of uPVC is that it is in no way environmentally friendly; in fact it uses petrol and natural gas in production and is sourced from rare fossil fuel deposits, so if you want to go a bit greener it is best to look elsewhere.
- Asphalt flat roofing – asphalt is a sticky, black liquid compound that is produced as a by-product during the melting and distillation processes of manufacturing crude oil. It can be blown with oxygen to form distinct shapes for use in the building industry. Asphalt is often used in roads and pavements but it has also proven effective as a flat roof material. A professional contractor can coat and cool an entire 5mx5m asphalt roof in less than a couple of days, making it a quick and easy option. Water will slowly degrade the roof’s surface, but fortunately asphalt can be easily recoated and repaired – and it costs as little as £50 to £180 per square foot.
- Waterproof felt flat roofing – formerly known as bitumous felt, waterproof felt is a synthetic, rubber-like material known as EPDM – Ethylene Propylene Diene Monomer. It is completely inflammable and has an inherent elasticity and strength, making it highly suitable for roofing on industrial properties such as warehouses. It is also extremely weatherproof, withstanding the long-term effects of both intense rain and sunshine, and it can be easily repaired if damaged. At anything between £70 to £200 per square foot, and with up to a fifty year guarantee, waterproof felt proves one of the most popular and versatile materials available.
- Fibreglass flat roofing – fibreglass, also known as Glass Reinforced Plastic (GRP), is a material manufactured out of a combination of various elements, but is primarily a fibre reinforced plastic resin that is intercut with fine fibres of glass for added strength and durability. This makes it extremely versatile and great for sheds and garages as well as larger industrial warehouses. Fibreglass is quick and easy to lay and can last for well over 20 to 30 years – making it a very dependable option too. Prices will be significantly higher than your other roofing options, but anything under £150 to £200 per square metres is actually something of a bargain.
Whatever material you choose, a professional contractor should have the roof laid in less than a week – and smaller warehouses in under a month. To make sure you get the best deal possible compare at least three quotes for the work.